The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Link: https://lore.kernel.org/r/20200220132017.GA29262@embeddedor
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that USB device drivers can reuse code from the generic USB device
driver, we need to make sure that they get selected rather than the
generic driver. Add an id_table and match vfunc to the usb_device_driver
struct, which will get used to select a better matching driver at
->probe time.
This is a similar mechanism to that used in the HID drivers, with the
generic driver being selected unless there's a better matching one found
in the registered drivers (see hid_generic_match() in
drivers/hid/hid-generic.c).
Signed-off-by: Bastien Nocera <hadess@hadess.net>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20191016093933.693-5-hadess@hadess.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The kernel currenly has only 2 usb_device_drivers, one generic one, one
that completely replaces the generic one to make USB devices usable over
a network.
Use the newly exported generic driver functions when a driver declares
to want them run, in addition to its own code. This makes it possible to
write drivers that extend the generic USB driver.
Note that this patch is not enough for another driver to automatically
get selected.
Signed-off-by: Bastien Nocera <hadess@hadess.net>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20191016093933.693-3-hadess@hadess.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The usb core is the only major place in the kernel that checks for
a non-NULL device dma_mask to see if a device is DMA capable. This
is generally a bad idea, as all major busses always set up a DMA mask,
even if the device is not DMA capable - in fact bus layers like PCI
can't even know if a device is DMA capable at enumeration time. This
leads to lots of workaround in HCD drivers, and also prevented us from
setting up a DMA mask for platform devices by default last time we
tried.
Replace this guess with an explicit HCD_DMA that is set by drivers that
appear to have DMA support.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20190816062435.881-4-hch@lst.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The USB buffer allocation code is the only place in the usb core (and in
fact the whole kernel) that uses is_device_dma_capable, while the URB
mapping code uses the uses_dma flag in struct usb_bus. Switch the buffer
allocation to use the uses_dma flag used by the rest of the USB code,
and create a helper in hcd.h that checks this flag as well as the
CONFIG_HAS_DMA to simplify the caller a bit.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20190811080520.21712-3-hch@lst.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that the driver core supports dev_groups for individual drivers,
expose that pointer to struct usb_device_driver to make it easier for USB
drivers to also use it.
Yes, users of usb_device_driver are much rare, but there are instances
already that use custom sysfs files, so adding this support will make
things easier for those drivers. usbip is one example, hubs might be
another one.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20190806144502.17792-3-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Clear_TT_Buffer request sent to the hub includes the address of
the LS/FS child device in wValue field. usb_hub_clear_tt_buffer()
uses udev->devnum to set the address wValue. This won't work for
devices connected to xHC.
For other host controllers udev->devnum is the same as the address of
the usb device, chosen and set by usb core. With xHC the controller
hardware assigns the address, and won't be the same as devnum.
Here we add devaddr in "struct usb_device" for
usb_hub_clear_tt_buffer() to use.
Signed-off-by: Jim Lin <jilin@nvidia.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull USB/PHY updates from Greg KH:
"Here is the big set of USB and PHY driver patches for 5.2-rc1
There is the usual set of:
- USB gadget updates
- PHY driver updates and additions
- USB serial driver updates and fixes
- typec updates and new chips supported
- mtu3 driver updates
- xhci driver updates
- other tiny driver updates
Nothing really interesting, just constant forward progress.
All of these have been in linux-next for a while with no reported
issues. The usb-gadget and usb-serial trees were merged a bit "late",
but both of them had been in linux-next before they got merged here
last Friday"
* tag 'usb-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (206 commits)
USB: serial: f81232: implement break control
USB: serial: f81232: add high baud rate support
USB: serial: f81232: clear overrun flag
USB: serial: f81232: fix interrupt worker not stop
usb: dwc3: Rename DWC3_DCTL_LPM_ERRATA
usb: dwc3: Fix default lpm_nyet_threshold value
usb: dwc3: debug: Print GET_STATUS(device) tracepoint
usb: dwc3: Do core validation early on probe
usb: dwc3: gadget: Set lpm_capable
usb: gadget: atmel: tie wake lock to running clock
usb: gadget: atmel: support USB suspend
usb: gadget: atmel_usba_udc: simplify setting of interrupt-enabled mask
dwc2: gadget: Fix completed transfer size calculation in DDMA
usb: dwc2: Set lpm mode parameters depend on HW configuration
usb: dwc2: Fix channel disable flow
usb: dwc2: Set actual frame number for completed ISOC transfer
usb: gadget: do not use __constant_cpu_to_le16
usb: dwc2: gadget: Increase descriptors count for ISOC's
usb: introduce usb_ep_type_string() function
usb: dwc3: move synchronize_irq() out of the spinlock protected block
...
The syzkaller fuzzer reported a bug in the USB hub driver which turned
out to be caused by a negative runtime-PM usage counter. This allowed
a hub to be runtime suspended at a time when the driver did not expect
it. The symptom is a WARNING issued because the hub's status URB is
submitted while it is already active:
URB 0000000031fb463e submitted while active
WARNING: CPU: 0 PID: 2917 at drivers/usb/core/urb.c:363
The negative runtime-PM usage count was caused by an unfortunate
design decision made when runtime PM was first implemented for USB.
At that time, USB class drivers were allowed to unbind from their
interfaces without balancing the usage counter (i.e., leaving it with
a positive count). The core code would take care of setting the
counter back to 0 before allowing another driver to bind to the
interface.
Later on when runtime PM was implemented for the entire kernel, the
opposite decision was made: Drivers were required to balance their
runtime-PM get and put calls. In order to maintain backward
compatibility, however, the USB subsystem adapted to the new
implementation by keeping an independent usage counter for each
interface and using it to automatically adjust the normal usage
counter back to 0 whenever a driver was unbound.
This approach involves duplicating information, but what is worse, it
doesn't work properly in cases where a USB class driver delays
decrementing the usage counter until after the driver's disconnect()
routine has returned and the counter has been adjusted back to 0.
Doing so would cause the usage counter to become negative. There's
even a warning about this in the USB power management documentation!
As it happens, this is exactly what the hub driver does. The
kick_hub_wq() routine increments the runtime-PM usage counter, and the
corresponding decrement is carried out by hub_event() in the context
of the hub_wq work-queue thread. This work routine may sometimes run
after the driver has been unbound from its interface, and when it does
it causes the usage counter to go negative.
It is not possible for hub_disconnect() to wait for a pending
hub_event() call to finish, because hub_disconnect() is called with
the device lock held and hub_event() acquires that lock. The only
feasible fix is to reverse the original design decision: remove the
duplicate interface-specific usage counter and require USB drivers to
balance their runtime PM gets and puts. As far as I know, all
existing drivers currently do this.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-and-tested-by: syzbot+7634edaea4d0b341c625@syzkaller.appspotmail.com
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
By moving one field around in 'struct urb' we reduce the size of the
structure by 8 bytes.
Before the patch on x86_64 the overall size of the structure as reported
by pahole was:
/* size: 192, cachelines: 3, members: 30 */
/* sum members: 184, holes: 2, sum holes: 8 */
After the patch we now have:
/* size: 184, cachelines: 3, members: 30 */
/* last cacheline: 56 bytes */
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, the USB hub core waits for 50 ms after enumerating the
device. This was added to help "some high speed devices" to
enumerate (b789696af8 "[PATCH] USB: relax usbcore reset timings").
On some devices, the time-to-active is important, so we provide
a per-port option to reduce the time to what the USB specification
requires: 10 ms.
Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The "old" enumeration scheme is considerably faster (it takes
~244ms instead of ~356ms to get the descriptor).
It is currently only possible to use the old scheme globally
(/sys/module/usbcore/parameters/old_scheme_first), which is not
desirable as the new scheme was introduced to increase compatibility
with more devices.
However, in our case, we care about time-to-active for a specific
USB device (which we make the firmware for), on a specific port
(that is pogo-pin based: not a standard USB port). This new
sysfs option makes it possible to use the old scheme on a single
port only.
Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB 3.2 specification adds Dual-lane support, doubling the maximum
SuperSpeedPlus data rate from 10Gbps to 20Gbps.
Dual-lane takes into use a second set of rx and tx wires/pins in the
Type-C cable and connector.
Add "rx_lanes" and "tx_lanes" variables to struct usb_device to store
the numer of lanes in use. Number of lanes can be read using the extended
port status hub request that was introduced in USB 3.1.
Extended port status rx and tx lane count are zero based, maximum
lanes supported by non inter-chip (SSIC) USB 3.2 is 2 (dual lane) with
rx and tx lane count symmetric. SSIC devices support asymmetric lanes
up to 4 lanes per direction.
If extended port status is not available then default to one lane.
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB SS and SSP hubs provide wHubDelay values on their hub descriptor
which we should inform the USB Device about.
The USB Specification 3.0 explains, on section 9.4.11, how to
calculate the value and how to issue the request. Note that a
USB_REQ_SET_ISOCH_DELAY is valid on all device states (Default,
Address, Configured), we just *chose* to issue it from Address state
right after successfully fetching the USB Device Descriptor.
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The URB_NO_FSBR flag has never really been used. It was introduced as
a potential way for UHCI to minimize PCI bus usage (by not attempting
full-speed bulk and control transfers more than once per frame), but
the flag was not set by any drivers.
There's no point in keeping it around. This patch simplifies the API
by removing it. Unfortunately, it does have to be kept as part of the
usbfs ABI, but at least we can document in
include/uapi/linux/usbdevice_fs.h that it doesn't do anything.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull sound updates from Takashi Iwai:
"There are no big surprising changes in this cycle, yet not too boring,
either. The biggest change from diffstat POV is the removal of the
legacy OSS driver codes that have been already disabled for a long
time. This will bring a few trivial merge conflicts.
As new features in ASoC side, there are two things: a new AC97 bus
implementation and AMD Stony platform support. Both include the
relevant changes shared with other subsystems, e.g. AC97 MFD changes
and DRM AMD changes.
Some other highlighted topics are:
- A bunch of USB-audio drivers got the hardening against the
malicious device accesses with a new helper code for endpoint
sanity check
- Lots of cleanups for ASoC Intel platform code, including support
for their open source audio firmware
- Continued ASoC core componentization works
- Support for scaling MCLK with sample rate in ASoC simple-card
- Stabler PCM hot-unplug capability, especially for ASoC usages"
* tag 'sound-4.15-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (302 commits)
Documentation: sound: hd-audio: notes.rst
ASoC: bcm2835: Support left/right justified and DSP modes
ASoC: bcm2835: Enforce full symmetry
ASoC: bcm2835: Support additional samplerates up to 384kHz
ASoC: bcm2835: Add support for TDM modes
ASoC: add mclk-fs support to audio graph card
ASoC: add mclk-fs to audio graph card binding
ASoC: rt5514: work around link error
ASoC: rt5514: mark PM functions as __maybe_unused
ASoC: rt5663: Check the JD status in the button pushing
ASoC: amd: Modified DMA transfer Mechanism for Playback
ASoC: rt5645: Wait for 400msec before concluding on value of RT5645_VENDOR_ID2
ASoC: sun4i-codec: fixed 32bit audio capture support for H3/H2+
ASoC: da7213: add support for DSP modes
ASoC: sun8i-codec: Add a comment on the LRCK inversion
ASoC: sun8i-codec: Set the BCLK divider
ASoC: rt5663: Delay and retry reading rt5663 ID register
ASoC: amd: use do_div rather than 64 bit division to fix 32 bit builds
ASoC: cs42l56: Fix reset GPIO name in example DT binding
ASoC: rt5514-spi: check irq status to schedule data copy in resume function
...
Pull USB/PHY updates from Greg KH:
"Here is the big set of USB and PHY driver updates for 4.15-rc1.
There is the usual amount of gadget and xhci driver updates, along
with phy and chipidea enhancements. There's also a lot of SPDX tags
and license boilerplate cleanups as well, which provide some churn in
the diffstat.
Other major thing is the typec code that moved out of staging and into
the "real" part of the drivers/usb/ tree, which was nice to see
happen.
All of these have been in linux-next with no reported issues for a
while"
* tag 'usb-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (263 commits)
usb: gadget: f_fs: Fix use-after-free in ffs_free_inst
USB: usbfs: compute urb->actual_length for isochronous
usb: core: message: remember to reset 'ret' to 0 when necessary
USB: typec: Remove remaining redundant license text
USB: typec: add SPDX identifiers to some files
USB: renesas_usbhs: rcar?.h: add SPDX tags
USB: chipidea: ci_hdrc_tegra.c: add SPDX line
USB: host: xhci-debugfs: add SPDX lines
USB: add SPDX identifiers to all remaining Makefiles
usb: host: isp1362-hcd: remove a couple of redundant assignments
USB: adutux: remove redundant variable minor
usb: core: add a new usb_get_ptm_status() helper
usb: core: add a 'type' parameter to usb_get_status()
usb: core: introduce a new usb_get_std_status() helper
usb: core: rename usb_get_status() 'type' argument to 'recip'
usb: core: add Status Type definitions
USB: gadget: Remove redundant license text
USB: gadget: function: Remove redundant license text
USB: gadget: udc: Remove redundant license text
USB: gadget: legacy: Remove redundant license text
...
ASoC: Updates for v4.15
The biggest thing this release has been the conversion of the AC98 bus
to the driver model, that's been a long time coming so thanks to Robert
Jarzmik for his dedication there. Due to there being some AC97 MFD
there's a few fairly large changes in input and the MFD layer, mainly to
the wm97xx driver.
There's also some drivers/drm changes to support the new AMD Stoney
platform, these are shared with the DRM subsystem and should be being
merged via both.
Within the subsystem the overwhelming bulk of the changes is in the
Intel drivers which continue to need lots of cleanups and fixes, this
release they've also gained support for their open source firmware.
There's also some large changs in the core as Morimoto-san continues to
mirror operations into the component level in preparation for conversion
of drivers to that.
- The AC97 bus has finally caught up with the driver model thanks to
some dedicated and persistent work from Robert Jarzmik.
- Continued work from Morimoto-san on moving us towards being able to
use components for everything.
- Lots of cleanups for the Intel platform code, including support for
their open source audio firmware.
- Support for scaling MCLK with sample rate in simple-card.
- Support for AMD Stoney platform.
Drivers who are interested in the PTM status stype, should use this
new helper to make sure they issue the correct GetStatus message.
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This new 'type' parameter will allows interested drivers to request
for PTM status or Standard status.
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This new helper is a simple wrapper around usb_get_status(). This
patch is in preparation to adding support for fetching PTM_STATUS
types. No functional changes.
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
